can i use a mk4 mfi xr3i head on a mk4 mfi rs turbo

are valves and cam the same

got to get my turbo on the road

the head has a faulty valve

and i have a xr3i engine

any one know

 

i believe cam is different and valves are sodium filled on a turbo

 

identical mate. cams are the same to, but the pulley is different on the turbo to give slightly more retard

 

it's only the s1's that had sodium filled valve's

 

sorry il get my coat

 

series ones had sodium valve seats and the RS turbo heads have round exhaust ports whereas XR's have D shaped ones.

 

Later heads had D shaped ports.... Not just 3i's

 

Im not shure that the cam is the same, i think it has lesser degrees and is made only for non turbo use, not sure though

 

cam is exactly the same as Rick said, its the pulley thats different

 

ok cheers so the only diference is cam pulley

 

 

What is the difference on the pulley?

 

It retards the cam timing a little on the RST

 

Sorry for bringing up this topic again!

How can I identify the pulley from a RST? Parts number, diameter, etc?

 

S1 RST heads are exactly the same like RS1600i ones. Same ports, same height and so on . S2 ones had the same specifications but hardened valve seats and most S2 also had sodium filled exhaust valves!

The height of RST and XR3i heads is different, so thats why there have been different camshaft pulleys

 

PeterRST


RST its a KA pulley

 

the rs1600i used solid lifters, not hydraulic...

 

Sure. And a rougher cam, other rockers, other inlet valves, a blanking plate for the dizzy side, standard exhaust valves and so on. But I talked about the HEAD, not the internals!

 

When you talk about the pulley being different, what will happen if someone where to use a xr3i pulley on the RST engine, please break it out in bits for me, im a retard when it comes to understanding things in english, not that i dont understand the words but its different to picture, if you know what i meen

 

arent you all forgeting about the combustion chamber shape?

rst are heart shaped, xr3i are hemi...

go to norris motorsport to check this out!

 

www.norrismotorsport.co.uk

 

All injected CVH engines, including RST, had the hemi head. You can convert to the arse-shaped chambers as shown on Karl's website, but RST surely came with the hemi chambers.

 

RS turbo heads all have the hemi chambers. lean burn heads, with kidney shaped chambers only came on later carb model cvh's

 

oh, and the lean burn heads arent favoured for tuning.

 

Heart shaped heads were found on many later 1.4i's like the PTE.

They wouldn't be that bad after all for tuning, especially the ignition would work well with these heads but you need the right piston crown for this...

 

say that to karl @ norrismotorsport...

 

Fuck really ive got more pulleys than i can shake a stick at and i have no idea which one is the RS one i picked the cleanest one Any way of telling them apart???

As for the heads they are 100% the same as are the valves (which AREN'T soduim filled) and the cams.

See this link for some more info and also some comic reading :

https://passionford.com/forum/viewto...r2i+heads+same